Re: [PATCH 4/6] arm: dts: karo: import dts for karo-qsxp-ml81

[Stefan Kerkmann <s.kerkmann@pengutronix.de>]

Hello Ahmad,

On 11.03.24 15:33, Ahmad Fatoum wrote:
> Hello Stefan,
> 
> On 11.03.24 15:23, Stefan Kerkmann wrote:
>> Hello Ahmad,
>>
>> On 11.03.24 11:02, Ahmad Fatoum wrote:
>>> Hello Stefan,
>>>
>>> On 11.03.24 10:10, Stefan Kerkmann wrote:
>>>> From: Marc Kleine-Budde <mkl@pengutronix.de>
>>>>
>>>> This imports the device tree for the Ka-Ro QSXP, which is a i.MX8M Plus
>>>> solder down system on module. The sources have been adapted from the
>>>> offical Ka-Ro github[1], commit a49b38ec97854c0cd9cd83a9f4ae3b56e99a58b6.
>>>>
>>>> [1]: https://github.com/karo-electronics/meta-karo-nxp.git
>>>
>>> To make it easier to sync with Linux, once the device tree goes upstream,
>>> could you separate the barebox-specific changes into a separate file?
>>>
>>
>> Ack.
>>
>>>> +	model = "Ka-Ro electronics QSXP-ML81 (NXP i.MX8MP) module";
>>>> +	compatible = "karo,imx8mp-qsxp-ml81", "fsl,imx8mp";
>>>
>>> Add a compatible for the SoM here: "karo,imx8mp-qsxp".
> 
> Then, why is it a DTS and not a DTSI?
> 

AFAIK, this was a request from Marc to keep it as a DTS. I have no
strong opinion here.

> 
>> You're right, AFAIK the eMMC JEDEC standard mandates 1.8V IOs for HS200
>> mode. For DDR mode the IO voltage can be 3.3V or 1.8V, according to the
>> datasheet of the used THGBMNG5D1LBAIL eMMC (if the product pictures are
>> anything to go by). So the correct voltage ranges property would be
>> `voltage-ranges = <1800 1800 3300 3300>`?
> 
> Your I/O Voltage (vccq) is fixed at 1.8V, so 3300 sounds wrong.
> 

Alright, but what if it wasn't and was adjustable? Just asking out of
curiosity.

>> The line itself was copied verbatim from
>> https://github.com/karo-electronics/meta-karo-nxp/blob/mickledore/recipes-kernel/linux/linux-karo-6.1/mx8-nxp-bsp/dts/freescale/imx8mp-karo.dtsi#L263
>>
>>
>>> Either way, it doesn't matter to barebox.
>> So in the end we just delete it?
> 
> Just delete it.
> 

Ack.

> Cheers,
> Ahmad
> 
>>
>>>> +	non-removable;
>>>> +	status = "okay";
>>>> +};
>>>> +
>>>> +&wdog1 {
>>>> +	pinctrl-names = "default";
>>>> +	pinctrl-0 = <&pinctrl_wdog>;
>>>> +	fsl,ext-reset-output;
>>>> +	status = "okay";
>>>> +};
>>>> +
>>>> +&iomuxc {
>>>> +	pinctrl_i2c1: i2c1grp {
>>>> +		fsl,pins = <
>>>> +			MX8MP_IOMUXC_I2C1_SCL__I2C1_SCL			0x400001c2
>>>> +			MX8MP_IOMUXC_I2C1_SDA__I2C1_SDA			0x400001c2
>>>> +		>;
>>>> +	};
> 
> 

Cheers,
Stefan

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